Starter mechanism



V. C. HODGE'S STARTER'MECHANISM April 21, 1942.

Filed July 17, 1841 INVENTOR.

KC. h/oc yes Q3 A TTOPNE Y Patented Apr. 21, 1942 @UNITED ,STATES PATENTOFFICE l 2,280,432 STARTER MECHANISM Vera C. Hodges, Los Angeles,Calif., assignor to H. P. Lester, Thomas B. Smallwood, and Vera l C.Hodges, doing business as Champion Aviation ProductsC'ompany, LosAngeles, Calif, a,

co-partnership Application july 17, 1941, SerialNo. 402,740 11 Claims.(cur-9) My invention relates to starter mechanism, andmore particularlyto starter mechanism for aircraft, and other appropriately gearedengines within the capacity of the starter mechanism.

An object of the invention is to provide in a starter mechanismyastraight, splined shaft for the purpose'of advancing the gearengagingportion of the starter mechanism, and to eliminate spiral splines orgrooves; Spiral grooves tend to permit chattering of groove engagingmemberspl which is desired 'to be eliminated l in the present invention.1 l

Other objects of theinvention are to provide starter means for aircraftthat is sturdy and affords an even pull, that is positive in operation,

convenient in use, easily installed in a working position, and easilydisconnected therefrom, economical of manufacture, relatively simple,and of general superiority and serviceability.

The invention also comprises novel details of construction and novelcombinations and arrangements of parts, which will more fully ,appear inthe course of the following description. Howeventhe drawing merely showsand the following descriptionmerely describes one e'mbodiment of thepresent invention, which is given by way of illustration or exampleonly.

In the drawing,likereference characters designate similar parts in theseveral views.

Fig. 1 is a longitudinal section through starter mechanism embodying thefeatures of the present invention, taken on the line I-l of'Fig. 5.

Fig. 2 is a broken elevationof apart of Fig. 1,

partly in section. 1

Fig. 3 is a'view similar to Fig. 2,'but showing a l different operativeposition. a, a a

Fig. 4 shows a succeeding operative position,

following that shown in Fig. 3. V

Fig. 5 is a transverse section taken on the line 55 of Fig. 1. l a

Referring more in detail .tothe drawing, the

. reference character 6 generally designates an em gine having a rotaryend-facedgear I. The clutch elements 8 of the gear 1 are disposed tobeenit tend to hold the head Ill away from the gear I of the engine. Thespring l5 is'mounted in the hollow portion I6 of the shaft l3 and abutsat oneend against a screw plug 11, in the hollow portion I5, of theshaft :I3, and at the other end abuts against ahead l8 on a bolt l9slidable in the plug IT. A sleeve 20 on the shank of the bolt 19 limitscompression of the spring I5. A nut 2| on the bolt l9 contacts the outerface of a washer 22. Through the intermediary of the mechanismdescribed, the spring l5 tends to draw ranged abuttingfaces 26 and 21which are arranged to engage abutting faces 28 and 29, respectively, onpointed integral 1ugs30 on the ring '24. Similar abuttingfaces andsimilar lugs are provided on the side of the mechanism opposite to thatshown.

The ring 24 is free to rotate upon the shank 23 of the? head [0, exceptfor limitations by the abutting faces 26 and 21 upon the lugs 30.However, a series of springs 3| is mounted on an in ner face of acylindricalflange 32 of a shell 33. r

The outer ends of the springs 3i are bolted to the flange 32, assuggested at 33. The innerends of the springs 3| have curved tips 34which frictionally engage the circumferential surface of the ring 24. Aninner race 35 and anouter race 36 for bearings 31 mountthe shaft l3 forrotation within, the shell 33. l

Clutch plates 38 and 39 alternately engage ribs 40 on the shaft l3 andribs 4| within the shell 33. A nut 42 upon the shaft l3. provides afixed abutment for the clutch plates. A movable head 43 is urged, bymeans of a spring 44, to cause the plates and 39 to frictionally engagewith one another. A nut 45, also on. the shaft i3, maintains a washer 46in position on the shaft, and provides a fixed abutment for the spring44. A gear 41,,likewise mounted on the shaft 13,. is driven by startermotor mechanism (not shown). A bearing 48 aids in supporting the shafti3.

In the operation of the mechanism, the starter motor drives the gear 41,which in turn rotates the shaft I3. Rotation of the shaft l3 causes thetherewith engaged head It also to rotate.

However, therotation of the clutch elements 9 in a counter-clockwisedirection, looking at same in the direction of the arrow A, causes theabutment faces 21, on the collar 25, to engage the abutment faces 29 on,the pointed lugs 30. Due to'the inclined arrangement of the faces 21 and29, the collar 25 and thereby the head H) are 7 moved outward upon theshaft i3, as best shown in Fig. 3.

When the head It! has been moved outward to the position shown in Fig.3,the clutch elements 9 engage the clutch elements 8 on the engine andturn the engine over. As soon as the engine 6 is operating by its owncombustion, the inclined surfaces 5! behind the clutch elements 8,engage the inclined surfaces 49 behind the clutch elements 9 and therebypush the starter head l away from starting position. Fig. 4 shows thestarter head It) returned to its original position after the engine 6has been started.

There is considerable tension upon the collar 24 by means of the springs3|; fact, there must be enough tension by means of these springs to holdthe head It against rotation upon rotation of the shaft 13. However, assoon as the engine 6 is rotating, there must be sufficient resilience inthe springs 3! to permit the head H) to retract and slide inward withregard to the flange 32.

The clutch provided by the plates 38 and 39 affords a safety means incaseof the kick-back of the engine 6. The nut 45 may be adjusted toregulate the tension of the spring 44, which in turn regulates thefriction between the plates 38 and 39.

It is believed clear that the present starter mechanism is reversible bymerely changing the direction of the clutch elements 8 and 9.

The spring I is a relatively weak spring and not strong enough to movethe head In inward with respect to the flange 32 against the action ofthe springs 3|, which are relatively stronger, at least in theiraggregate, than the relatively weak spring l5.

While I have illustrated and described what I now regard as thepreferredembodiment of my invention, the construction is, of course, subject tomodifications without departing from the spirit and scope of myinvention. I, therefore, do notwish to restrict myself to the particularform of construction illustrated and described, but desire to availmyself of all modifications which may fall within the scope of theappended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. In starter mechanism,. a shaft having straight splines longitudinallythereof, a starter head meshing with the splines on the shaft and havinga longitudinal sliding movement with respect to the shaft, the starterhead having an inclined portion, an element normally substantiallystationary during forward movement of the starter head, the elementhaving inclined means arranged to engage the inclined portion of thestarter head and to feed the starter head forward, upon rotation of thestarter head by means of the shaft.

2. In starter mechanism, a shaft having straight splines longitudinallythereof, a starter head having a rearwardly extending member providedwith an inclined end face facing rearwardly with respect tosaid member,the starter head meshing with the splines on the shaft and having alongitudinal sliding movement with respect to the shaft, an elementnormallysubstantially stationary during forward movement of the starterhead, the element engaging the inclined portion of the starter head andarranged by reason of suchinclined portion to feed the starter headforward, upon-rotation of the starter headby means'of theshaft.

3. In starter mechanism, a shaft having straight splines longitudinallythereof, a starter head having an abutment face, the starter headmeshing with the splines on the shaft and having a longitudinal slidingmovement with respect to the shaft, an element normally substantiallystationary during forward movement of the starter head, the elementhaving inclined means arranged to engage the abutment face of thestarter head and to feed the starter head forward, upon rotation of thestarter head by means of the shaft.

4. In starter mechanism, a shaft having straight splines longitudinallythereof, a starter head meshing with the splines on the shaft and havinga longitudinal sliding movement with respect to the shaft, the starterhead having a rearwardly extending collar provided with an inclinedportion spaced inward from the end of the collar, an annular elementupon the collar to the rear of the inclined portion but engaging withthe inclined portion, and means arranged to maintain the elementsubstantially stationary during forward movement of the starter head.

5. In starter mechanism, a shaft, 8. starter element connected to rotatewith the shaft but having a movement lengthwise with respect to theshaft, an element arranged to be held relatively stationary duringforward movement of the starter element, at least one of the elementshaving an inclined portion and the other element having an abutting faceengaging the inclined portion on the other element, arranged to effectsaid forward movement of the starter element by rotation of the shaft,and means disposed frictionally to substantially prevent movement of thesecond mentioned element during rotation of the shaft effecting forwardmovement of the starter element.

6. In starter mechanism, a shaft having straight splines longitudinallythereof, a starter element meshing with the splines on the shaft andhaving a longitudinal sliding movement with respect to the shaft, anelement arranged to be movable during return movement of the starterelement, at least one of the elements having an inclined portion and theother element having an abutting face engaging the inclined portion onthe other element, arranged to effect forward movement of the starterelement by rotation of the shaft, and means disposed frictionally tosubstantially prevent movement of the second mentioned element duringrotation of the shaft effecting forward movement of the starter element.

7. In starter mechanism, a shaft, a starter element connected to rotatewith the shaft but having a movement lengthwise with respect to theshaft, an element arranged to be held relatively stationary duringforward movement of the starter element, at least one of the elementshaving an inclined portion and the other element having an abutting faceengaging the inclined portion on the other element, arranged to effectsaid forward movement of the starter element by rotation of the shaft,and resilient means disposed to resiliently resist movement of thesecond mentioned element during rotation of the shaft effecting forwardmovement of the starter element.

8. In starter mechanism, a shaft having straight splines longitudinallythereof, a starter element meshing with the splines on the shaft andhaving a longitudinal sliding movement with respect. .to .the shaft, .anelement arranged to ,be movable adoring return. mnyement. of the starterelement, at least one of the elements having an inclined portion and theother element having an abutting face engaging the inclined portion onthe other element, arranged to effect forward movement of the starterelement by rotation of the shaft, and resilient means disposed toresiliently resist movement of the second mentioned element duringrotation of the shaft effecting forward movement of the starter element.i

9. In starter mechanism, a shaft, a starter element connected to rotatewith the shaft but having a movement lengthwise with respect to theshaft, an annular element arranged to be movable during return movementof the starter element, at least one of the elements having an inclinedportion and the other element having an abutting face engaging theinclined portion on the other element, arranged to effect forwardmovement of the starter element by rotation of the shaft, the annularelement having a circumferential face of substantially the same diameterthroughout its length, providing a substantially smooth outer surface,and resilient means frictionally engaging the said outer surface of theannular element and resisting movement of suchelement during rotation ofthe shaft effecting forward movement of the starter element.

- 10. In starter mechanism,a shaft, a starter element connected torotate with the shaft but having a movement lengthwise with respect tothe shaft, the starter element having a rearwardly extending collar, anannular element rotatable upon the collar, at least one of the elementshaving an inclined portion and the other element having an abutting faceengaging the inclined portion on the other element, arranged to effectsaid forward movement of the starter element by rotation of the shaft,and resilient means frictionally engaging the said outer surface of theannular element and resisting movement of such element during rotationof the shaft effecting forward movement of the starter element.

11. In starter mechanism, a shaft, a starter element connected to rotatewith the shaft but having a movement lengthwise with respect to theshaft, relatively weaker spring means tending to move the starterelement along the shaft away from its engine-starting position, arelatively movable element normally substantially stationary duringrotation of the shaft, at least one of the elements having an inclinedportion and the tively stronger spring means than the first-mentionedspring means resiliently resisting rotation of the second-mentionedelement during rotation of the shaft.

VERA C. HODGES.

